Search: 555 timer

The two circuits illustrate using the 555 timer to close a relay for a predetermined amount of time by pressing a momentary N/O push button. The circuit on the left can be used for long... [more]

This 555 timer circuit toggles a relay when a button is pressed. Pins 2 and 6, the threshold and trigger inputs, are held at 1/2 the supply voltage by the two 10K resistors. When the... [more]

This is a basic 555 squarewave oscillator used to produce a 1 Khz tone from an 8 ohm speaker. In the circuit on the left, the speaker is isolated from the oscillator by the NPN... [more]

These two circuits are multi-range timers offering periods of up to 24 hours and beyond. Both are essentially the same. The main difference is that when the time runs out, Version 1 energizes the relay... [more]

This is a programmable clock timer circuit that uses individual LEDs to indicate hours and minutes. 12 LEDs can be arranged in a circle to represent the 12 hours of a clock face and an... [more]

This circuit provides a visual 9 second delay using a 7 segment digital readout LED. When the switch is closed, the CD4010 up/down counter is preset to 9 and the 555 timer is disabled with... [more]

The purpose of this circuit is to power a lamp or other appliance for a given time (30 minutes in this case), and then to turn it off. It is useful when reading at bed... [more]

circuit from:http://www.extremecircuits.net/2009/12/bedside-lamp-timer-circuit-schematic.html

This timer was designed for people wanting to get tanned but at the same time wishing to avoid an excessive exposure to sunlight. A Rotary Switch sets the timer according to six classified Photo-types (see... [more]

circuit from:http://www.extremecircuits.net/2009/12/tan-timer-circuit-diagram.html

This circuit turns-off an amplifier or any other device when a low level audio signal fed to its input is absent for 15 minutes at least. Pushing P1 the device is switched-on feeding any appliance... [more]

circuit from:http://www.extremecircuits.net/2010/01/amplifier-timer-circuit-schematic.html

he purpose of this circuit is that of power a lamp or other apparatus for a given time (30 minutes in this case), and then to turn it off. [more]

This timer will provide a sequence of up to ten separate events. The length of each event is set independently. And the sequence will run a fixed number of times - or repeat continuosly. The... [more]

This device is a simple timer, allowing to keep on the headlights of your vehicle for about 1min. and 30sec., e.g. when accessing some dark place, without the necessity of coming back to switch-off the... [more]

This circuit was developed since a number of visitors of this website requested a timer capable of emitting a beep after one, two, three minutes and so on, for jogging purposes. As shown in the... [more]

A switched timer with equal make and equal space periods timing adjustable from over 6 minutes to 38 minutes. [more]

This clock timer uses a PIC16F628 microcontroller to display 3 and 1/2 digit time and control an external load. The clock includes a calendar with leap year and optional daylight savings adjustments. The timer output... [more]

Relay Timer switch [more]

This circuit has an adjustable output timer that will re-trigger at regular intervals. The output period can be anything from a fraction of a second to half-an-hour or more - and it can be made... [more]

This circuit is very similar to Repeating Interval Timer No.2 . However - the addition of a light dependent resistor means that the operation of this timer can be limited to the daylight hours. A... [more]

This circuit is a temperature controlled version of Repeating Timer No.3 . The light dependent resistor has been replaced by a temperature dependent resistor or thermistor. And a small preset potentiometer lets you choose the... [more]

This timer was deliberately designed for people wanting to get tanned but at the same time wishing to avoid an excessive exposure to sunlight. [more]